Wheel with central brake



Dec. 16, 1,941. y J, A RQC'H 2,266,079

WHEEL WITH CENTRAL BRAKE Filed July 2. 1940 2 sheets-sheet 1 v Frs. 2'. l

\ s4/v A Pag-Hs TRA/Gm l 16,- 1941. J. A. ROCHE WHEEL WITH GENTRAL BRAKE 2 sheets-sheet 2` Filled July 2, 1940 heavy wheel, or side nular tire supp `v and further serve mission of l Patented Dec. 16, 1941 UNITED STATES Pa'rau'r fori-ica 2,266,019 warm. wml esami. 'nam Jean A. Broch, Langley Field, Va.

1940, serial No. 343,565 s claims. (ci. isa-1s) Application July 2,

(Granted The invention described herein may be m'anufactured and used by or for the Government for governmental me of any royalty thereon.

This invention relates to A a novel wheel and brake assembly having a particular utility' for use on aircraft though not limited thereto.

In aircraft wheel and brake assemblies now in use, great dimculty is experienced in obtaining an adequate braking surface since the present brakes of the wheel within brake width the increase of brake width causes an of the load supporting portions of the wheel and thus increases the liability of wheel' failure under load stresses. This diiliculty is overcome in accordance with the invention by constructing the wheel in the form of spaced forged or cast discs, or side members, rotatably moimtedon the axle and having the rim, or anmember between the side members. Within laterally extending brake rim or tire supporting by the fact, that eccentricity the wheel a drum is secured to the member inner surface of the brake surface adapted to cocentral spider secured to the axle. The spider also" es as a support for the `iiuid pressure brake motor and the braise shoe retracting springs. ll'he spider is pro 'ded with radial arms which serve as guides for the brake shoes as a means to support the tire supporting member under loads suiiicient to 'cause an appreciable deforma ion or the said member. The brake drum and shoes are arranged substantially symmetrically with respect to the vertical centerline of the wheel and the brake shoes apply a substantially radial pressure and introduce no 4appreciable bending moment into the side members.

It is thus seen that in the improved structure above described no limitation is placed on the size of the brake except the space between the side members and the inner diameter of the tire supporting member, so that 'a brake of adequate dimensions may be secured in a wheel of maximum strength.

A further feature of the invention is the provision in a wheel of the type above described of an annular brake drum having an outside diameter less than the inside porting rim and secured to the rim in a manner to permit a free circulation of air from the space within the wheel through the'space between the brake drum and the rim to prevent the transheat through the rim to the tire and in wheelsof large size, to provide for admission of air adjacent the axle and for discharge of air in concentric rei under the act of March amended April 30, 1928; 370 0.

, without the payment to'y i extending laterally diameter of the tire suptaining the wheel of pressure to the inner surface of extension of s, ists, as G. 'z5-1)V 4 the wheel, the wheel side members to create a circulaassoc lated adjacent the outer periphery of radial bracing webs on the forming a centrifugal pump tion of air over the brake drum. and p in which of a pair of spaced side memmounted on the axle and secured to a tire supporting rimlocated between the side members, thewheel enclosing a lateral annular brake'drum secured to and disposed substantially symmetrically with respectto the vertical median line of the wheel and the provision of internal brake mechanism-supported by the axle for applying a radial braking the brakedrum.

A further object of the invention is the provision in a wheel and brake assembly of the type described of a means ,to minimize the transmission of heat from the annular brake drum to the tire supporting rim.

A further object of the invention is the provision ina wheel of the above described type of an theside membersbeyond the rim to form tire retaining rim anges and of a means to detachably connect. the outer side member to an annular ring, rigidly secured to the rim, whereby a tiremay be rapidly mounted and demounted. A further object of the invention is the provision in a wheel andbrake assembly of the type described of a structure forming a centrifugal pump, to create a current of cooling air over the internal brake drum and its associated parts.

A furtherobject of the invention is the provision of anarrangement of the brake supporting structure and wheel side brake operating mechanism may connected and from the axle.

A furtherl object of the invention is the provision 'in a wheel and brake assembly of the type described of a hand hole through the outer side member to facilitate the manual adjustment ofv the brake without removal of the wheel.

Other features and objects of the invention, not specifically set forth above, will parent by reference to the following detailed description and the appended drawings 'in which:

Figure l is a side elevation of the wheel and brake construction according to the invention, a the outer side member being broken away to show the internal construction; and

Figure 2 is a sectional view taken on line 2-2 of Figure 1;. and

be readily distheentire wheel quickly removed isometric view of the central brake supporting spider; and

Figure 4 is a-detail of a modiiied means for re- Figure l on the axle.

Referring now to the devices illustrated in arts. e The principal object of the invention is the the tire supporting rim y members that the become ap- 4 Figures 1 to 3 inclusive, the numeral I a landing gear strut provided with a ting Ia, at is socketed represents a conventional hollow stub axle 2.

, bolts 2|, which thread into the bosses I9. The side member 22 is provided with an enlarged radially extending portion 23, which serves the function of a rim flange similar to the portion I2 of the side member 6. The wheel side member 22 is provided with a central enlarged boss 25 suitably counterbored for a bearing 26 of the same type as bearing 8. A nut 21, threaded on the end of axle 2 within the counterbore ofsthe side member 22, serves to retain the wheel in its assembled relation on the axle 2. 'I'he wheel side member 22, is provided with radially extending Webs 24 to by a removable cover plate 30, access to the nut 21 for removing the same.

vThe side members and 22, in conjunction With the deep-well rim II, form a complete wheel assembly. A pair of annular flanged rings 32, having inwardly directed flanges 33, are riveted in spaced relation to the inner side of the wheel rim I 'I. The inwardly directed flanges 33 are pierced by a plurality of holes 34, which,serve An annular brake is secured to the inwardly directed at the outer portions thereof, preferably by welding or otherwise. This construction thus provides an air space 31 between the rim I1 and the annular brake drum 35. The inner annular surface of the brake drum 35 is adapted to be contacted by an annular ring cf brake lining material 36 to form the well-known lining is freely vertical medium line of the wheel assembly.

A spider, generally indicated by the reference numeral 40, is provided with a central hub portion 42, having internal splines 45, and is socket flt- A the lower end thereof and in which is connected through mounted on the central spline portion 4 of the axle 2, and retained radial guides 44. The spider 40 is provided with a vertically extending web 46 tofwhich is secured the pivotal links 53 and 54, which in turn are connected to the opposite ends of the brake shoe 50. The upper link 54 is. pvoted as at 55 to the fluid pressure brake motor 58, which is also mounted on the web 46 by means of rivets or the like. A flexible yfluid pressure conduit 60, having a removable coupling 5I at its inner end, a transverse bore in the axle 2 to a tting 63 the spider 40, from contact the brake drum 35.

In order to render the brake adjustable from the exterior of the mounting and demounting of the Wheel fromthe axle.

It will be noted that the space 31 brake drum 35 and the wheel wheel in large heavy loaded braking loads are able to incorporatemeans providing an additional supply of cooling air. The entrance of this additional supply of cooling air tothe interior of the wheel is provided by means of a series of ports 15 drilled through the outer side member 22 adjacent the hub 25 thereof. A

means to discharge heated air from the interior of the wheel is provided by a plurality of ports 16 drilled through the inner side member 6 adjacent the outer ends of the Webs lil. It will be seen that when the'wheel assembly 'is rapidly ro- 2'1, which secures the bearing 2B inthe same tating, that the radial webs Il and 24 of the l wheel side members 6 and 22 respectively, will form in effect a centrifugal air pump, tending to create an increased pressure at the outer periphery of the wheel and to create a reduced air pressure within the wheel adjacent its axis of rotation. Since the air under pressure may escape through the ports 16, a continual circulation of air from the outside atmosphere through the port 16, through the chamber- 31 and mhacent brake structure, towards the discharge .ports 16 will take place in the manner indicated by the arrows in Figure 2. This stream of air will further insure adequate cooling of the brake drum and associated brake lining and brake shoe, greatly adding to their service life.

From the above described construction, it is obvious that the only limitation on the size of brake employed is the spacing between the wheel side members 6 and 22, respectively, andthe dimanner as the'nut 21 in the construction of Figures 1 and 2. The threaded plug 2,1' is locked against rotation by means of the locking ring 28, which is held by suitable splines 29, on the end of the reduced diameter portion 5 of the axle 2. 1 The threaded plug 21', is secured to the locking ring 28 by a conventional locking wire 30. The

defined by the appended claims will become apparent to those skilled in the art.

ameter of the brake 'drum 35 which is limited..

only by the diameter of the well portion of therim l1. These limitations arev such, however, that a brake of much larger dimensions than has heretofore been used in the art is possible and the structure, in accordance with the invention, is a solution to the problem of obtaining an adequate braking surface without the usual eccen- Mtricity of the load supporting portions of the wheel, relative to the plane of application of the vertical wheel load. The construction further is I claim:

1. A wheel and brake assembly comprising an axle, a pair of spaced disc side members rotatably mounted on said axle, a laterally extending annular tire supporting member located between said side members and secured thereto in concentric relation to said axle to form a closed Wheel, an annular laterally extending brake drum having its inner surface forming afbraking surface and secured to said annular tire supporting member in a manner to form an air space therebetween communicating at each end thereof with the interior of the wheel, radial webs on each of j said side members extending Within the wheel interior and forming centrifugal pump impeller vanes, and means to admit air to the interior of adapted to forged construction of the wheel side members, the integral internal radial webs add- .and demounted. When replaced, the -ange 23 of the side member 22 again serves` its usual function of a tire retaining rim iiange.

The construction of the brake mechanism per se and the means for supplying uid pressure to actuate the brake form no part of the present invention, since other types of brake mechanism than those specically illustrated are suitable for l use with the structure in accordance with the invention.

In addition to the spider 40 serving as a support for the brake shoe 50 in the event of `an excessive wheel load occurring of such a magnitude as to cause a partial collapse of thewheel., an amount equal to the clearance space 52, the

enlarged portions 44 of the spider 80 will be contacted by the brake shoe 50' and will serve to transmit some of the radial wheel loads directly the wheel adjacent the axis of rotation of one of said side members and means to discharge air from the interior of said wheel located adjacent the outer peripheral portion of the other of said side -members, whereby rotation of said wheel `causes a flow of air through said air space to reduce the transmission of heat from said brake drum tosaid tire supporting member.

2. In a wheel and brake assembly, 'an axle, a.

pair of spaced disc side members rotatablyv mounted on said axle, a laterally extending annular tire supporting member located between said side members and secured thereto in concentric relation to said axle to form a closed wheel,. an annular laterally extending brake drum located vbetween said side members and having its inner surface -forming a braking surface, said brake drum being secured to said tire supporting member in a manner to form an annular air space therebetween having free communication at the ends thereof with the interior of said wheel to allow a free circulation of air through said air space and to isolate a substantial amount of the heat developed in the brake drum from reaching said tire receiving member.

3. The structure as claimed in claim 2, in which said side members are provided with apertures to permit the free access of air to the interior of said wheel.

- JEAN A. noem. 

